Drill bit



Oct. 19, 1954 c. M. KUCERA ET AL DRILL BIT 4 Sheets-Sheet 1 Filed Nov. 13, 1951 a Mr 6 K m MP 6 T. i b mo R m m w.

A TTOR/VE VJ Oct. 19, 1954 C. M. KUCERA ET AL DRILL BIT '4 Sheets-Sheet 2 Filed Nov. 13, 1951 C/emenz M A ucefa Robe/f 6; Pezer INVENTORJ Oct. 19, 1954 c, KUCERA -r' 2,692,117

DRILL BIT Filed Nov. 13, 1951 4 Sheets-Sheet 3 I C/emenz M Kucera fiche/f 6 Pefer INVENTORS Oct. 19, 1954 c. M. KUCERA ET AL DRILL BIT 4 Sheets-Sheet 4 Filed Nov. 13, 1951 INVENTOR-S ATTORNEY) Patented Oct. 19, 1954 UNITED STATES PATENT OFFICE DRILL BIT Clement M. Kucera and Robert G. Peter, Houston, Tex., assignors to Reed Roller Bit Company, Houston, Tex., a corporation of Texas Application November 13, 1951, Serial No. 255,918

15 Claims.

This invention relates generally to drill bits, and particularly to roller bits for drilling deep .wells in the earth.

The roller bits now in common use (for example, the so-called cross roller bit and the cone bit) embody a bit head in which rollers are rotatably mounted. The bit head is connected to the end of a drill stem which is rotated to cause the rollers to roll upon the bottom of the hole and thereby cut or crush the formation. A mudladen drilling fluid is pumped downwardly through the drill stem and bit, and rises upwardly in the space between the drill stem and the wall of the hole to the surface of the earth. One of the most important desired functions of the drilling fluid thus circulating is quickly to remove the cut or crushed particles of the formation from the bottom of the hole and from the rollers and the adjacent walls of the head. This function is not always efficiently performed, because in various formations, particularly in sticky shales, the particles of the formation adhere to the rollers and accumulate between the rollers and the adjacent walls of the head, as a result of which the rollers either cease to rotate and are worn by skidding upon the bottom of the hole, or the abrasive particles of the formation wear away the rotating ends of the rollers, the adjacent stationary walls of the head, and the bearings of the rollers. This failure of the mud-laden drilling fluid to perform this desired function occurs in various types of roller bits, and particularly in those roller bits in which the mud-laden drilling fluid is discharged from the bit head upon the bottom of the hole.

This invention has for one of its general objects the provision of a new and improved roller bit through which the drilling fluid will freely circulate to perform the desired function of quickly removing the particles of formation from the bottom of the hole and from the head and the rollers.

The roller bits in common use are heavy and hard to handle, but it is necessary that they be handled by the men on the rig, particularly when they are screwed on or off the drill stem.

This invention has for another of its general objects to provide a new and improved roller bit which may be easily handled by the men on the rig and easily screwed on or off the drill stem.

Other objects will hereinafter appear.

The preferred embodiments of the invention are illustrated by the accompanying drawings in which Figs. 1 through 6 illustrate the invention embodied in a cross roller bit and Figs. 7

2 through 12 illustrate the invention embodied in a cone bit.

Figs. 1, 2 and 3 are perspective views of the cross roller bit;

Fig. 4 is a fragmentary view illustrating the drilling fluid discharge passageways;

Fig. 5 is a bottom plan view; and

Fig. 6 is a fragmentary view illustrating the drilling fluid exit passageway adjacent the upper outer portion of the side roller;

Figs. 7, 8 and 9 are perspective views of the cone bit;

Fig. 10 is a fragmentary view illustrating the drilling fluid discharge passageways;

Fig. 11 is a bottom plan view; and

Fig. 12 is a fragmentary view illustrating the drilling fluid exit passageway adjacent the upper outer portion of the cone.

Referring first to the cross roller bit shown in Figs. 1 through 6, the bit head is indicated at I. It may be provided with the usual threaded shank 2 for attachment to the drill stem (not shown). The head I has a pair of oppositely disposed depending cross roller bearing extensions 3 and 4 on which are rotatably mounted the cross rollers 5 and 5. The head also has a pair of oppositely disposed depending side roller bearing extensions 1 and 8 on which are rotatably mounted the side rollers 9 and Ill. The side rollers are rotatable on axes inclined downwardly and inwardly from the upwardly and inwardly inclined inner walls of the bearing extensions 1 and 8 so that the upper portion of the side rollers is at a substantial distance from the periphery of the head. The side rollers and cross rollers may be rotatable in the usual manner on suitable pins (not shown). The outer ends of the pins may be supported in the usual manner by the depending bearing extensions 3, 4, 1 and 8 and the inner ends may be connected by the usual bridge II. The bearing extensions 1, 8, 9 and I!) of the head form a recess for the rollers.

Drilling fluid pumped downwardly through the drill stem (not shown) passes through the bore l2 of the threaded shank and thence through the nozzles I4 and I 5 by which it is discharged downwardly toward the bottom of the hole.

One of the most important desired functions of the drilling fluid is to keep the rollers clean and to quickly remove from the bottom of the hole the particles of material cut or crushed by the rollers, and to convey these particles of the formation upwardly between the drill stem and the wall of the hole to the surface of the earth. This desired function has not always been performed by the drilling fluid in the conventional cross roller bit because particles of the formation have been trapped between the side rollers 9 and I and their bearing extension I and 8, and these particles have accumulated in the head above the side rollers particularly when the bit has been; used in sticky shales, as'at result of which the-side rollers have been prevented from rotating, or the abrasive particles of formation have worn the side rollers, the side roller bearing extensions and associated parts. To prevent.

this, this invention may be embodied in the conventional cross roller bit by; providing special:

side roller bearing extensions-l: and 8;. Ittwill be noted that these extensions are provided'with special drilling fluid exit passageways it and. I"!- er 9. The-drilling fluid discharged downwardlyv toward the bottom of: the-ahole. by-thedrilling.

fluid discharge-passageways l 4 and l 5 will quickly remove from the bottom of the hole the par ticles-zofzformation cut: ortcrushed by the rollers, and these particles will=not accumulate within the head abovewthe.rollers-because they will not be trapped :therei-n but on the contrary will move with the drilling; fluid outwardly through the drilling fluid exit openingsr lfi andll.to;be.car.--

ried to. the. surface of; the earth; Invother. words thedrilling fluid will .bezpermittedto thus circulate into the recess of the head above :the.rollers andthence-from the1-interior'to the exterior. ofttherhead'throughthe. exit openings I6 andill. and-thereby perform its important. and desired.

function above'referred to.-

It willbe'notedthat'the sideroller bearing; extension increases in. thickness zupwardly to; thepointiat which the drilling fluid exit-passageway is providedand that zample strength to. 'supportv the: side roller. 9 1 is thus afiorded. Itwill i also be; noted that the .head l tapersv inwardly r and. upwardly substantially at the; point where theodrilllng fluid-exit passageway, 16- issprovidedr so. that. the drilling. fluid-carrying the particles of the formation may move freely: through the. drilling; fluid exit passageway. l6 and thence up wardly, in the .-ascending column of :drilling; fluid It willalso. be" noted that the drilling fluid wilLmoveout of :the recessrformed. by the bearingv extensions substantially axiallyof theaside roller. il -through the drilling fluid: exitpassageway I 6'- so a that the" roller 9 will be": kept clean and the particles of the formation to. the surface;

will not accumulate .in the recessrdefined .bythe bearing.- extensions.

The opening I6 is of such size and the walls ofv theopening are. so .rounded as to providezacom venient handle which may be graspedby the handof the man on .the .rig who is handlingthe bit... This will make veryhcavybits. easy to handle; The. openings I6..and.ll are oppositely disposed,and..if desired .any suitable lever bar. may be inserted throughopenings I6 and I1 'toscrew the. threaded shank 2. of.the bit into and out of the; drill stem. This will. render unnecessary the use .of any; special tools for connecting and dis-- 4 connecting the threaded shank from the drill stem.

Referring now to Figs. 7 through 12 which illustrate the embodiment of the invention in a cone bit the bit head is indicated at 21. It may be provided with the usual threaded shank 22 fforattachment to thee drillfstem (not shown). The head 21- has three depending bearing extensions 23, 24 and 25. Rotatably mounted on these extensions 23, 24 and 25 and rotatable on axes inclined downwardly and inwardly from the upwardly and inwardly inclined inner walls of said extensions. are* three substantially conical rollersa26;.21lcant-1:128. These substantially conical rollers maybe-supported on the bearing extensicnsimthewelleknown manner by suitable pins. Drilling fluid pumped downwardly through the drill stem (not shown) passes through the bore 29 of the shank 22?and thence through the nozzles 38, 3 I and. 32V .by which it; is. discharged downwardly toward the-bottom of the-hole. To. cause the desired circulation ofithedrilling fluid. from the recess .of. the. head .deflned by.=the hearing, extensions 23-, 2-4 and. 2.5 :so that. the: rollers.

will be. kept: clean .and .the particles of the. fore mation .cut .or crushed {thereby willv not accumu-- late :in theerecess, .this invention. is. embodied .in the. bit. described byproviding; a drilling. fluid.

exit passageway in the head. adj acentthe upper. outer. portion oteach of:the=.r011ers.26, 21.- and;

28; The. drilling, fluid. exit passageway; above.

the when 26; -is-. indicated at- 33-, the.drilling..fluid. exit passageway abovethe .roller: 21' is; indicated. att34- and .the drilling fluid .exitpassagewayabove. the roller.- 28: by..thenumeral 35. The drilling. fluid dischargedzdownwardlytoward the: bottom.

of the :hole. by the drilling fluid discharge. passageways-tfl, 31 and.32 will circulatefromithe.

recess. of the head. formed by, the .bearing extensions outwardly,- through each of the drilling; fluid exitpassageways inra. direction substantial-.-

ly,in.the;plane ofthe .axis .of rotationof rollers.

adjacent .thereto..

Theropenings. 33, 34. and. 35 andthe walls. thereof will form convenient handlesfor handling .the -bit,,and a lever bar may be .inserted. therein forthe purpose. of screwing. .theishankezl.

intoand out ofthe drill stem;-

It. will be apparent. from the. foregoing; that. the invention will be. found particularly useful: inibitsembodying rollers, dependingzlugs and. tubes toxdischarge. slush downwardlynear. the: wall of .-the hole; because these :elementssubstantially fill the .bore of the hole.v

The; invention is .not limited to the. embodiments herein disclosed... Variouschanges,- .with.- in: thescope:- of the following claims, will occur 7 to. those; skilled in the art;

We claim:

.l. A cross :roller bitzhavinggahead; ,sa-id-headri having two oppositely disposed dependinggc-ross-e rollerbearingextensions; and two opp x disposed side roller bearing extensions; crossz rollersmounted on the lower portions of said .cross discharge passageway to discharge drilling fluidtoward the bottom ofvthe hole; and. each of said sidearoller bearing extensionshavingwa drilling fluid exit passageway adjacent the upperouter.

portion of the side .roller. mounted thereon.

2. .Acrossrollerbit.having. a.head,. cross rollers 51. and side rollers mounted on bearing extensions on the lower portion of said head, said head having a drilling fluid discharge passageway and drilling fluid exit passageways formed in certain of said extensions adjacent the upper outer portions of the rollers carried thereby.

3. A cone bit having a head, said head having three depending bearing extensions; and a substantially conical roller mounted on each of said extensions on an axis inclined downwardly and inwardly from said extensions, said head having a drilling fluid discharge passageway to discharge fluid toward the bottom of the hole, and each of said bearing extensions having a drilling fluid exit passageway adjacent the upper outer portion of the roller mounted thereon.

4.- A cone bit having a head, and substantially conical rollers mounted on bearing extensions on the lower portion of said head, said head having a drilling fluid discharge passageway and drilling fluid exit passageways formed in certain of said extensions adjacent the upper outer portions of said rollers.

5. A roller bit having a head with a roller recess in the bottom thereof, one of the inner walls of said recess being inclined upwardly and inwardly toward the longitudinal axis of the head, and a roller mounted on said wall, said head having a drilling fluid exit opening through said wall above said roller, and a drilling fluid discharge passageway, whereby drilling fluid may flow into said recess above said roller and out of said recess through said exit opening.

6. A roller bit having a head with a roller recess in the bottom thereof, and a roller mounted in said recess, said head having a drilling fluid discharge passageway, and an exit opening through the wall of said recess adjacent the upper outer portion of said roller, whereby drilling fluid may flow into said recess above said roller and out of said recess substantially axially of said roller through said exit opening.

7. A roller bit having a head, said head having a recess in the bottom thereof, a roller cutter mounted on one of the walls of said recess to rotate adjacent said wall, and means to discharge drilling fluid downwardly toward the bottom of the hole, said head having a drilling fl-uid exit passageway adjacent the upper outer portion of said cutter and communicating with said recess and the space between the head and the wall of the hole so that drilling fluid laden with cuttings will flow from said recess through said passageway into said space.

8. A roller bit having a head, said head having a recess in the bottom thereof defined in part by an upwardly and inwardly inclined wall, a roller cutter mounted on said wall in said recess to rotate adjacent said wall on an axis inclined downwardly and inwardly, and means to dis charge drilling fluid downwardly toward the bottom of the hole, said head having a drilling fluid exit passageway adjacent the upper outer portion of said cutter and communicating with said recess and the space between the head and the wall of the hole so that drilling fluid laden with cuttings will flow from said recess through said passageway into said space.

9. A roller bit having a head, said head having a recess in the bottom thereof, a plurality of rotatable cutters mounted in said recess, said recess being defined in part by an upwardly and inwardly inclined wall, at least one of said cutters being mounted on said wall in said recess to rotate adjacent said wall on an axis inclined downwardly and inwardly, and means 'to dis-' charge drilling fluid downwardly toward the bottom of the hole, said head having a drilling fluid exit passageway adjacent the upper outer portion of said cutter and communicating with said recess and the space between the head and the wall of the hole so that drilling fluid laden with cuttings will flow from said recess through said passageway into said space.

10. A cone bit having a head, said head having a recess in the bottom thereof, a plurality of substantially conical cutters mounted in said recess, said recess being defined in part by upwardly and inwardly inclined walls, each of said cutters being mounted on one of said walls in said recess to rotate adjacent said wall on an axis inclined downwardly and inwardly, and means to discharge drilling fluid downwardly toward the bottom of the hole, said head having a drilling fluid exit passageway adjacent the upper outer portion of each of said cutters and communicating with said recess and the space between the head and the wall of the hole so that drilling fluid laden with cuttings will flow from said recess through said passageways into said space.

11. A cone bit having a head, said head having a recess in the bottom thereof, a. plurality of substantially conical cutters mounted in said recess, said recess being defined in part by upwardly and inwardly inclined walls, each of said cutters being mounted on one of said walls in said recess to rotate adjacent said wall on an axis inclined downwardly and inwardly, and means to discharge drilling fluid downwardly toward the bottom of the hole, said head having a drilling fluid exit passageway adjacent the upper outer portion of at least one of said cutters and communicating with said recess and the space between the head and the wall of the hole so that drilling fluid laden with cuttings will flow from said recess through said passageway into said space.

, 12. A cross roller bit having a head, said head having a recess in the bottom thereof, cross roller cutters and side roller cutters mounted in said recess, said recess being defined in part by upwardly and inwardly inclined walls, said side roller cutters being mounted on said walls in said recess to rotate adjacent said walls on axes inclined downwardly and inwardly, and means to discharge drilling fluid downwardly toward the bottom of the hole, said head having a drilling fluid exit passageway adjacent the upper outer portion of each of said side roller cutters and communicating with said recess and the space between the head and the wall of the hole so that drilling fluid laden with cuttings will flow from said recess through said passageways into said space.

13. A cross roller bit having a head, said head having a recess in the bottom thereof, cross roller cutters and side roller cutters mounted in said recess, said recess being defined in part by upwardly and inwardly inclined walls, said side I roller cutters being mounted on said walls in said recess to rotate adjacent said walls on axes inclined downwardly and inwardly, and means to discharge drilling fluid downwardly toward the bottom of the hole, said head having a drilling fluid exit passageway adjacent the upper outer portion of at least one of said side roller cutters and communicating with said recess and the space between the head and the wall of the hole so that drilling fluid laden with cuttings will flow from 7 said recessuthrough .said :passageway ainto :sa-id space.

514. 'A-:.cross.ro11er bitrhavingt a head,-said head having-a recess .in. the bottom thereof ,cross roller cuttersand ,sideflroller cutters mounted in said recess,::means tondischarge drilling -fluid=1downwardlytoward the bottom of the. hole,-saidi head having a drillingfiuid exit; .passageway; adjacent;

the upper outer portionhoft-atsleast one of: said roller cutters and communicating with said recess andrthespaoe between: the "head andt-hewallnof thevholerso that drilling fluid ladentwith cuttings will fiow-from'said recess through said passageway into said space.

:15.. Aroller bit having ahead; said head having a. recess the lower portion thereof, a v plurality of: roller. cutters mounted in said recess,- means tosdisoharge drilling fluid downwardly toward the hottomiofi thec-hole, theesaid.head laa'vfingzaadrilling nfiuidgpassageway sad-jaeent .s the upper neuter portion ,ofaatdeast :one: of f theelsaich when outteass and communicating-iwithtthe said recess andthe space-between theasaidehead andthevwallr ofethe hole so that drilling; fluidwandqcuttingsa maywirculate through the: said passageway.

mefenences Gited in r thefile of-tms vpatent "UNITEDSTATESPATENTS Number Name i Date 322,642 7 Reese. July;21,r1'885 1,120,198 d-Iumason Decn8, 11914 1,182,533 :Double. v ..:Mayv9, .1916 2,072,627 1 Zublin Mar.:2, .-;2-',165,-5.84 :Smith;:et-sa1. -'Ju1y.:11, 1939 2,260;487 Scott -i Qct. 228,.11941 

